Hem-folding attachments



April 7, 1959 A. M. GARDNER 2,880,685

HEM-FOLDING ATTACHMENTS T Filed Feb. 17. 1956 2 uvmvroa.

'9- Augusf M. Gardner W/ TNESS A TTOVBNEY United States PatentHEM-FOLDING ATTACHMENTS August M. Gardner, Elizabeth, N.J., assignor toThe Singer'Manufacturing Company, Elizabeth, N.J., a

H corporation of New Jersey ApplicationFebruary 17, 1956, Serial No.566,189

1 Claim. (Cl. 112---141) This invention relates to overedge sewingmachines and more particularly to 'means embodied therein forhem-folding the marginal portions of both fiat and tubular work-piecesand for so presenting the folded workpieces to the trimming and stitchforming mechanisms that the projecting edge portion of each work-pieceis trimmed substantially in line with the fold and the hem is secured tothe body material by a blind-stitch overedge seam.

A primary object of the invention is to provide an improved hem-folderwhich, although most efficient in operation, is at the same time adaptedto be applied readily to a conventional type of sewing machine withoutthe necessity of adding to the machine any special fittings in the wayof brackets, bolts, clamps or the like.

Another object of the invention is to providesuch a hem-folderattachment that may be swung about a horizontal axis to the end that thefolder may be removed from its operable position thereby to facilitatecertain sewing operations.

With the above and other objects in view, as will hereinafter appear,the invention comprises the devices, combinations and arrangements ofparts hereinafter set forth and illustrated in the accompanying drawingsof a preferred embodiment of the invention, from which the severalfeatures of the invention and the advantages attained thereby will bereadily understood by those skilled in the art.

In the drawings:

Fig. 1 represents a fragmentary top plan view of a portion of anoveredge sewing machine fitted with the present hem-folder.

Fig. 2 represents, on an enlarged scale, a left-hand elevational view ofa presser-foot employed in the present machine, which resser-foot hasincorporated therein the present hem-folder.

Fig. 3 represents, on an enlarged scale, a right-hand elevational viewof the presser-foot with the present hemfolder attached thereto.

Fig. 4 represents a front elevational'view of-the device disclosed inFig. 2.

Fig. 5 represents a sectional view taken substantially along the line5-5 of Fig. 3.

Referring to the drawings, the invention is shown as embodied in anoveredge sewing machine of the type disclosed in the U. S. patent of N.Knaus, No. 2,238,796, April 15, 1941. Furthermore, the present inventionrepresents an improvement over the hem-folding attachment disclosed inthe U. S. patent of N. Knaus et al., No. 2,649,066, August 18, 1953.

Referring to Fig.1 of the drawings, the sewing machine partiallyillustrated therein comprises a usual type of overedge sewing machinecomprising a base frame portion and an upstanding portion 12. The baseportion 14 carries a horizontally disposed work-supporting plate 13 anda throat-plate 14 provided with slots (not herein shown) through whichoperate the usual feed-dogs which, since they do not form a part of thepresent invention, are not disclosed herein. The main frame alsosupports the usual overedge stitch-forming mechanism including areciprocatory curved needle 15 and an overedge loop ice 2 spreader 16which cooperates with the needle "15 in the formation of overedgestitches.

The present overedge stitching machine also includes a conventionalpresser device comprising a horizontally disposed spring-depressedpresser-bar 17 pivoted at its rear end to the machine frame andcarryingat its forward end a presser-foot 18 which overlies the throatplate 14and the feeding mechanism which is not herein disclosed.

The machine further includes a trimming mechanism adapted to trim thework at one side of the line of seam formation. The trimming mechanismincludes a vibratory trimmer bar 119-actuated from the main shaftofthecm'achine and carrying at its forward end a "movable trimmer blade20 which cooperates with a stationary trimmer blade carried by the baseportion of the-machine frame and not disclosed herein. Inasmuch as thespecific constructions of the stitch-forming, work-feeding andworktrimming mechanisms are shown in the above mentioned Knaus PatentNo. 2,238,796 andform no part of the present invention, furtherillustration and description thereof is deemed unnecessary.

As hereinabove indicated, this invention relates primarily to improvedmeans, provided in the machine of the type above described, for sopresenting a work-piece to the stitch-forming mechanism that themarginal portion of the work is folded into flattened S shape, with theuppermost portion thereof trimmed substantially in verical alignmentwith the lowermost fold. The needle 15 thereupon penetrates the upperpart of the work adjacent the trimmed edge and passes through theunderlying .fold entering and then merging from the same face of thework, all in a manner as described in the above noted Knaus et a1.Patent No. 2,649,066. I

The present hem folder is adapted to be secured upon the sewing machineresser-foot 18. This presser-fo'ol comprises an elongated sole-plate 21which is provided in its upper portion with the groove 22 for receivingtherein the depending portion 23 of the .presser-ba'r 17 about which thepresser-foot is pivotally mounted. The resser-foot 1% is maintained inits pivotal relation relative to the presser-bar by means of'an arm 24secured to the presser-foot by means of a screw 25. Referringparticularly to Fig. 1, it will be noted that the arm 24 extendsrearwardly so as to overlie a laterally extending portion 26 of thepresser-bar thereby 'to'provide a pivotal connection between thepresser-bar and the .presser-foot.

Projecting upwardly from the forward end of the soleplate 21 is aninclined presser-foot ftoe 27, the upper'portion of which is providedwith a groove 23 which is disposed crosswise of the presser-foot and ofthe direction of work feed. As will hereinafter be described, thisgroove 28 is adapted for receiving therein a member which carries thepresent hem-folder device. For a more complete description of a pressermechanism of the present type, reference may be had to the U. S. patentof N. Knaus, No. 2,41%,494, April 22, 1947.

A preferred form of the present hem-folder device com prises asubstantially L-shaped platform member includ ing limbs 29 and 30.Referring particularly to Figs. and 2, the limb 29 is slidably mountedWithin the resserfoot toe groove 28 and is adapted to be secured .in aselected position of crosswise adjustment of the presserfoot by means ofa screw 31 which passes freely through an elongated slot 32 provided inthe limb 29. The limb 30 has formed therein a cylindrical'opening 33which is disposed in parallelism with the direction of work feed and inwhich is rotatably mounted a stub shaft 34. As best disclosed in Fig. 3,the left-hand end portion of the shaft 34 is provided with an enlargedhead 35 while the right-hand end portion of the shaft passes out of thelimb 30 and is secured imposition by means of a 'cfillar 36 and a setscrew 37 which locks the collar in position upon the distal end portionof the shaft 34. Formed crosswise of the head portion 35 of the shaft 34is a cylindrical aperture 38 which, as will be hereinafter described,carries a wire hem-folder element. The free end portion of the shafthead 35 is appropriately threaded to receive a set screw 39 which, aswill hereinafter be described, functions to lock the wire edge folderwithin the aperture 38.

The present hem-folding portion of the attachment includes ahorizontally disposed U-shaped wire member including upper and lowerlimbs 41 and 42, of which the lower limb 42 is adapted to enter betweenthe plies of the folded work and hold the folded right-hand edge of thework against a floating edge guide of the type provided in the machinedisclosed in the above U.S. patent of Knaus, No. 2,238,796. Theleft-hand folded edge of the work engages the crotch portion 43 of theU-shaped wire member. More specifically, the present hem-folder elementcomprises a length of wire which is bent intermediate its two ends intoa substantially U-shaped member including the above noted upper andlower limbs 41 and 42, which member receives the inner fold of thework-piece. It will be observed that the limbs 41 and 42 of the U-shapedmember are disposed when in their operable position, as disclosed inFig. 4, in substantial parallelism with the plane defined by the loweror active face of the presser-foot 18. The free end portion of the upperlimb 41 enters the aperture 38 provided in the head portion 35 of thestub shaft 34 and may be locked in a selected position within saidaperture by means of the set screw 39. From this it will be appreciatedthat the U-shaped wire member may be adjusted crosswise of the directionof feed in either one of two ways. For example, the entire U-shapedmember together with the L-shaped platform element may be shiftedcrosswise of the direction of feed by adjustment of the lock-screw 31.An alternative adjustment is to shift the wire member within theaperture 38 and thereafter lock it in a selected position by means ofthe set screw 39.

The free end portion of the lower limb 42 is bent at right angles to theplane defined by the first U-shaped member and forms an arbor 44 aboutwhich the outer fold of the work-piece is wrapped. This arbor 44 is bentbackwardly from the first U-shaped member in the line of scam formationand, as is best disclosed in Figs. 1 and 2, it terminates at a locationdirectly beneath the upwardly inclined toe portion 27 of thepresser-foot. Thus, this wire hem-folding unit is carried entirely bythe presserfoot and after it is properly adjusted relative to the footby means of the screw 31 it forms an integral part of the foot.Referring particularly to Figs. 1, 2 and 3, it will be observed that thearbor portion 44 of the hem-folder is slabbed at its upper and lowerportions 45 and 46 so as to give a tapered effect to the arbor in orderto facilitate the passage of work thereabout. Also, it will be observedfrom Fig. 4 that the lower surface 47 of the lower limb 42 is slabbed soas to reduce the diameter of the lower limb in order to facilitate thepassage of work thereabout.

By mounting the present hem-folder wire upon the presser-foot, anintegral unit is produced which, in re sponse to actions of thefeed-dog, will pivot about the presser-bar and facilitate the passage ofwork therethrough. Also, it will be appreciated that as variations occurin the work, such as due to cross seams, the present hem-folder devicewill be permitted to move up and down with the presser-foot so asproperly to accommodate such work.

Those skilled in the art will readily appreciate that sometimes it isdesirable to employ such an edge-folder intermittently and, thus, it ishelpful if such a device can be thrown into and out of operation withoutremoving the same from the sewing machine or the presser-foot itself. Inorder to facilitate such operations the present wire hem-folder may beswung from its operative posi- '4 tion as disclosed in solid lines inFig. 4 to an inoperative position as is illustrated by the dotted lineview of Fig. 4.

More specifically, the wire edge-folder is maintained in its operativeposition as disclosed in Fig. 4 due to the fact that the upper limb 41rests upon a lip portion 48 carried by the limb 30 of the platformmember. When the operator wishes to remove the wire edge-folder from itsoperative position, it is merely necessary to grasp the crotch portion43 thereof and swing it in a clockwise direction as viewed from Fig. 4so that the unit will swing about a horizontal axis provided by therotary shaft 34. As may be best observed from Figs. 1 and 4, theclockwise movement of the wire hemmer will be arrested by a stop element49 formed on the outer extremity of the platform limb 30.

Referring particularly to Figs. 1, 3 and 5, means are provided forreleasably locking the wire edge-folder element in its retractedposition. This means includes a substantially L-shaped spring includinglimbs 50 and 51, of which the limb 50 is secured directly to the limb 30of the platform member by means of a screw 52. As may be best seen inFig. 5, the limb 51 of the spring is adapted to engage the shaft collar36 which is secured to the shaft 34 in a manner such that a slabbedportion 53 thereof will be engaged by the limb whenever the wireedge-folder is in its operable position. From this, it will beappreciated that the limb 51 of the spring will function to maintain theedge-folder in its operable position but that the operator may readilyovercome the force of the spring and shift the edge-folder to itsinoperable position by a mere flick of the finger.

From the above, it will be understood that the present device is notonly most efficient in use but at the same time it presents a unit whichmay be most economically manufactured and exploited commercially.

Having thus set forth the nature of the invention, what I claim hereinis:

A sewing machine hemming attachment comprising, a presser-foot includingan elongated flat-bottomed soleplate, and a toe projecting from theforward end of and being inclined upwardly relative to the fiat bottomof the sole-plate; a shaft disposed lengthwise of the sole-plate; meansmounting the shaft upon the elevated end of the presser-foot toe forturning movements about its longitudinal axis; a work-folding memberincluding a length of wire bent intermediate its two ends into asubstantially U-shaped member whose two limbs when in operative positionare disposed in substantial parallelism with the plane defined by theflat bottom-surface of the sole-plate and with the plane defined by thetwo limbs disposed at all times at right angles to the plane defined bythe flat bottom surface of the sole-plate; the free end portion of afirst limb of the member being bent at right angles to the plane definedby the two limbs and extending when the member is in its operativeposition lengthwise of the sole-plate and terminating directly in frontof and beneath the level of the top of the inclined presser-foot toe;means securing the free end portion of the second limb of the memberupon the shaft whereby the member may be swung upwardly about the shaftaxis and away from its operative position to an inoperative positionwherein the free end of the first mentioned limb is disposed above thelevel of the top of the inclined presser-foot toe; and means carried bythe presser-foot toe releasably maintain ing the shaft and thework-folding member in their operative and inoperative positions.

References Cited in the file of this patent UNITED STATES PATENTS359,452 Lavigne Mar. 15, 1887 877,659 Maus Jan. 28, 1908 2,649,066 Knauset a1 Aug. 18, 1953 FOREIGN PATENTS 115,884 Sweden Feb. 19, 1946

